I know there's a thread kinda about this already and I read it to an extent but was wondering what maybe new guys or vets who didn't respond thought.  Is there a huge drop when playing someone who is in their low 90's (fatigue) as opposed to between say 97-100%.  I usually don't rest a position guy until he is under 89 unless one of my AAA is playing really well, i'm playing a weak team or I am up by a lot in the standings.  To be honest I still see a lot of my players perform well anywhere from 88-92%.   

As far as my pitchers go I try not to start any starters unless they are above 89%, is it a horrible thing to have them starting when they are in the low 90's?  I also let my RP pitch as long as they are at or above 88% and as long as they have been performing all year I rarely see any fall off.  A lot of the time if they are between 84-87% and having good years i'll set them for said game as Setup B, usually they aren't used and raise their fatigue so I can put them back as Setup A.  

Also another question....I've only really used Closers a few times or the title closer a few times.  I prefer to set ALL my bullpen guys to Setup A and let it play out.  I usually have had success (nothing HOF type but good success) doing this, w/ the only other spot being differing in my pen is i'll have a 200k guy or AAA as a mop up.  Does anything feel this is hurting more then helping my teams?  Do you feel there SHOULD ALWAYS be a closer in there (not saying I don't have players who were closers, just don't set them as closers).  

Fielders will make more errors once they get below 100% - it can be pretty significant by the time you get to 90%. But I don't really see much drop-off in hitting when you get into the mid-90s. So I might play my RF/LF/1B guys down a little lower.

I try not to get my SPs below 98% or so, but that's just because I want them at 100% for the playoffs and if they get down too low, they might not recover. I set most of my relievers to 80% autorest, but again, if you have a guy who pitches at 81, rests, pitches at 81, rests, etc.. the results won't be as good.

I used to belong to the "no closer" school as well. In "real" baseball, it makes sense to put your best reliever into the highest leverage situation. That might be 2 on, 1 out in the 7th inning. But in sim baseball you can't control the leverage that your relievers are used for. You might have a setup B in a tight spot in the 6th inning. So I've started using a closer on the assumption that on average, the highest leverage situations will be in the 9th inning.

Sometimes my closer won't be my best reliever, but he'll be close. I want very specific things from my closer - low HR9 and low walks. I don't mind if he gives up a hit or two as long as he doesn't make a huge mess. Think Mike Williams or Hal Haid. I also want them to be somewhere between 45-60 innings. If I'm doing a theme league and the best relievers available don't fit that criteria, then my setup A might actually be a "better" pitcher than my closer.